1. Field of the Invention
The present invention is directed to an adjustable rotational coupling apparatus, and, more particularly, to a coupling apparatus for aligning a mounting plate and axis of a shaft with respect to a specific reference location.
2. Description of the Related Art
Alignment of a shaft mounted mounting plate with respect to a specific reference location is a problem that has been previously recognized. One specific application where this has been a problem involves a machine used to weld two halves of a torque converter together. Such a machine is disclosed in pending U.S. application Ser. No. 07/522,891 filed May 14, 1990, now U.S. Pat. No. 5,000,366, the matter of which is incorporated by reference herein.
As disclosed in FIG. 1, the welding machine 10 includes a fixed shaft 12 and a telescoping shaft 14. A chuck 16 is mounted to the fixed shaft 12 and a face plate 18 is mounted to the telescoping shaft 14. A transmission side cover 20 of the torque converter can be mounted in the chuck 16 and an engine side cover 22 of the torque converter is loosely positioned against the cover 20. The telescoping shaft can then be extended as shown in FIG. 2 to clamp the two covers 20 and 22 of the torque converter together. Cover 22 includes a pilot shaft 23 and a plurality of mounting lugs 25. A central axis of the pilot shaft 23 is the central axis of the cover 22. A pump drive tube 21 attached to the transmission side cover 20 is the central axis of the cover 20 which is accurately located with respect to a central axis of chuck 16. Therefore, the positioning of the central axis of the cover 22 is accomplished by inserting the pilot shaft 23 into a locating bore (not shown) in the face plate 18/shaft 14 assembly as the shaft 14 is telescoped to clamp the two covers 20 and 22 together. The mounting lugs 25 pressingly engage the face of the face plate 18 to position the cover 22 and establish a plane in which the cover 22 rotates. Both shafts 12 and 14 are then rotated together at approximately 1 r.p.m. while the two covers 20 and 22 of the torque converter are welded together.
For the finished torque converter to operate optimally, it is necessary for the two covers 20 and 22 to be accurately aligned with each other before welding. This requires that shaft 14 and face plate 18 be accurately aligned with respect to shaft 12 and chuck 16. For proper alignment, the central axis of the locating bore must be concentric with a central axis of the chuck 16 and a plane in which the face plate 18 rotates must be perpendicular to the central axis of the chuck 16.
The chuck 16 is a conventional "AJUST-TRU" chuck, which can be adjusted so that the central axis of the chuck 16 is concentric with the central axis of the shaft 12. However, in the conventional welding machine 10, the face plate 18 is rigidly attached to the shaft 14. All adjustments to insure the true travel of the moving shaft 14 on the central axis of the chuck 16, the precise centering of the locating bore to be truly concentric with the central axis of the chuck 16 and to gain a true perpendicular plane of the face plate 18 to the central axis of the chuck 16 must be made within the mounting of the shaft 4 in the framework of machine 10. Additionally, accurate machining is necessary to insure the true perpendicular plane of the face plate 18 to the outer diameter of the shaft 14 and true concentricity of the inner diameter of the face plate 18 to the outer diameter of the shaft 14.
Therefore, it is possible for the central axis of the locating bore to not be concentric with the central axis of the chuck 16 and/or for the plane in which the face plate 18 rotates to not be perpendicular to the central axis of the chuck 16. Further, since the shaft 14 rotates, any misalignment of the shaft 14 is magnified by a lever arm effect due to the length of the shaft 14 when it is telescoped to clamp the two torque converter covers 20 and 22 together. Thus, these inaccuracies are introduced into the alignment of the two torque converter covers 20 and 22, resulting in a less than optimal final torque converter assembly.